December 2007 arXiv papers — page 37

Ariel Megevand, Alejandro D. Sanchez

Cosmological phase transitions are predicted by Particle Physics models, and have a variety of important cosmological consequences, which depend strongly on the dynamics of the transition. In this work we investigate in detail the general features of the development of a first-order phase transition. We find thermodynamical constraints on some quantities tha

R. Umstaetter, M. Tinto

We estimate the probability of detecting a gravitational wave signal from coalescing compact binaries in simulated data from a ground-based interferometer detector of gravitational radiation using Bayesian model selection. The simulated waveform of the chirp signal is assumed to be a spin-less Post-Newtonian (PN) waveform of a given expansion order, while th

Gianguido Dall'Agata, Nikolaos Prezas, Henning Samtleben, Mario Trigiante

We propose a universal geometric formulation of gauged supergravity in terms of a twisted doubled torus. We focus on string theory (M-theory) reductions with generalized Scherk-Schwarz twists residing in the O(n,n) (E_{7(7)}) duality group. The set of doubled geometric fluxes, associated with the duality twists and identified naturally with the embedding ten

Christopher D. Carone, Ashwin Rastogi

We consider a gauge extension of the electroweak sector of the Standard Model based on the group G_2 x SU(2)x U(1). The exceptional group G_2 is the smallest rank two group that contains SU(3) as a subgroup; the SU(3) prediction sin^2 theta_w=1/4 follows approximately in this model if the couplings of the additional SU(2) and U(1) factors are sufficiently la

Valery A. Lunts

We provide proper foundations and proofs for the main results of [Ka]. The results include a flat base change for formality and behavior of formality in flat families of $A(\infty)$ and DG algebras.

I. Assani, Z. Buczolich

Let $(X,\mathcal{B}, μ, T)$ be an ergodic dynamical system on a non-atomic finite measure space. We assume without loss of generality that $μ(X)=1.$ Consider the maximal function $\dis R^*:(f, g) \in L^p\times L^q \to R^*(f, g)(x) = \sup_{n\geq 1} \frac{f(T^nx)g(T^{2n}x)}{n}.$ We obtain the following maximal inequality. For each $1<p\leq \infty$ there exists

Robert L. Singleton

A completely rigorous first-principles calculation of the charged particle stopping power has recently been performed by Brown, Preston, and Singleton (BPS). This calculation is exact to leading and next-to-leading order in the plasma number density, including an exact treatment of two-body quantum scattering. The BPS calculation is therefore extremely accur

Gerardo Aldazabal, Anamaria Font

We show that a class of type IIA vacua recently found within the N=4 effective approach corresponds to compactification on Ads_4 \times S^3 \times S^3/Z_2^3. The results obtained using the effective method completely match the general ten-dimensional analysis for the existence of N=1 warped compactifications on Ads_4 \times M_6. In particular, we verify that

N. Nettelmann, B. Holst, A. Kietzmann, M. French

The equation of state of hydrogen, helium, and water effects interior structure models of giant planets significantly. We present a new equation of state data table, LM-REOS, generated by large scale quantum molecular dynamics simulations for hydrogen, helium, and water in the warm dense matter regime, i.e.for megabar pressures and temperatures of several th

J. J. Rodriguez-Vega, W. A. Zuniga-Galindo

We give a multimensional version of the p-adic heat equation, and show that its fundamental solution is the transition density of a Markov process.

Wojciech Broniowski, Enrique Ruiz Arriola, Krzysztof Golec-Biernat

We evaluate Generalized Parton Distributions of the pion in two chiral quark models: the Spectral Quark Model and the Nambu-Jona-Lasinio model with a Pauli-Villars regularization. We proceed by the evaluation of double distributions through the use of a manifestly covariant calculation based on the alpha representation of propagators. As a result polynomiali

Gordon Blower

Suppose that $\Gamma$ is a continuous and self-adjoint Hankel operator on $L^2(0, \infty)$ and that $Lf=-(d/dx(a(x)df/dx))+b(x)f(x)$ with $a(0)=0$. If $a$ and $b$ are both quadratic, hyperbolic or trigonometric functions, and $\phi$ satisfies a suitable form of Gauss's hypergeometric equation, or the confluent hypergeometric equation, then $L\Gamma =\Gamma L

Sourish Basu, Erich J. Mueller

We model the impact of final state interactions on the radio frequency spectrum of a strongly interacting two-component superfluid Fermi gas. In addition to a broad asymmetric peak coming from the break-up of Cooper pairs we find that, for appropriate parameters, one can observe a sharp symmetric &#34;bound-bound&#34; spectral line coming from the conversion

Fabricio Macia

In this article we study limits of Wigner distributions (the so-called semiclassical measures) corresponding to sequences of solutions to the semiclassical Schroedinger equation at times scales $α_{h}$ tending to infinity as the semiclassical parameter $h$ tends to zero (when $α_{h}=1/h$ this is equivalent to consider solutions to the non-semiclassical Schre

J. Rodriguez, J. A. Tomsick, S. Chaty

(Abridged) We made use of X-ray observations with the X-ray telescope on-board the \swift observatory to refine the X-ray position to 3-5&#34; accuracy of 12 INTEGRAL sources, so as to further identify their counterpart at optical, infrared, and radio wavelengths, to try to unveil their true nature. We then searched the online catalogues (e.g. NED, SIMBAD, 2

Nelson Faustino, Uwe Kaehler

Based on \cite{DH94}, we introduce a bijective correspondence between first order differential calculi and the graph structure of the symmetric lattice that allows one to encode completely the interconnection structure of the graph in the exterior derivative. As a result, we obtain the Grassmannian character of the lattice as well as the mutual commutativity

P. A. Ritto

A tetra of sets which elements are time series of interbeats has been obtained from the databank Physionet-MIT-BIH, corresponding to the following failures at the humans&#39; heart: Obstructive Sleep Apnea, Congestive Heart Failure, and Atrial Fibrillation. Those times series has been analyzed statistically using an already known technique based on the Wavel

W. Caudy, J. Greensite

Local gauge symmetries cannot break spontaneously, according to Elitzur&#39;s theorem, but this leaves open the possibility of breaking some global subgroup of the local gauge symmetry, which is typically the gauge symmetry remaining after certain (e.g. Coulomb or Landau) gauge choices. We show that in an SU(2) gauge-Higgs system such symmetries do indeed br

A. Mobius

In a recent experiment, Lai et al. [Phys. Rev. B 75, 033314 (2007)] studied the apparent metal-insulator transition (MIT) of a Si quantum well structure tuning the charge carrier concentration $n$. They observed linear temperature dependences of the conductivity $σ(T,n)$ around the Fermi temperature and found that the corresponding $T \to 0$ extrapolation $σ

A. S. Rodrigues, P. G. Kevrekidis, Mason A. Porter, D. J. Frantzeskakis

Motivated by recent proposals of ``collisionally inhomogeneous&#39;&#39; Bose-Einstein condensates (BECs), which have a spatially modulated scattering length, we study the existence and stability properties of bright and dark matter-wave solitons of a BEC characterized by a periodic, piecewise-constant scattering length. We use a ``stitching&#39;&#39; approa

Lee Smolin

We study a unification of gravity with Yang-Mills fields based on a simple extension of the Plebanski action to a Lie group G which contains the local lorentz group. The Coleman-Mandula theorem is avoided because the theory has no global spacetime symmetry. This may be applied to Lisi's proposal of an E8 unified theory, giving a fully E8 invariant action. Th

M. Johanning, A. Braun, D. Eiteneuer, Chr. Paape

Neutral Ytterbium (YbI) and singly ionized Ytterbium (YbII) is widely used in experiments in quantum optics, metrology and quantum information science. We report on the investigation of isotope selective two-photoionisation of YbI that allows for efficient loading of ion traps with YbII. Results are presented on two-colour (399 nm and 369 nm) and single-colo

V. Limic, P. Tarres

We offer a reader-friendly introduction to the attracting edge problem (also known as the &#34;triangle conjecture&#34;) and its most general current solution of Limic and Tarrès (2007). Little original research is reported; rather this article ``zooms in&#39;&#39; to describe the essential characteristics of two different techniques/approaches verifying the

Charlie Conroy, Jeremiah P. Ostriker

A variety of physical heating mechanisms are combined with radiative cooling to explore, via one dimensional hydrodynamic simulations, the expected thermal properties of the intracluster medium (ICM) in the context of the cooling flow problem. Energy injection from type Ia supernovae, thermal conduction, and dynamical friction (DF) from orbiting satellite ga

Nuo Yang, Gang Zhang, Baowen Li

The thermal conductivity of silicon nanowires (SiNWs) is investigated by molecular dynamics (MD) simulation. It is found that the thermal conductivity of SiNWs can be reduced exponentially by isotopic defects at room temperature. The thermal conductivity reaches the minimum, which is about 27% of that of pure 28Si NW, when doped with fifty percent isotope at

A. Morozov

A short review of basic formulas from Hamiltonian formalism in classical mechanics in the case when Lagrangian contains N time-derivatives of n coordinate variables. For non-local models N=infinity.

Stephen Doty, Jun Hu

We prove Schur--Weyl duality between the Brauer algebra $\mathfrak{B}_n(m)$ and the orthogonal group $O_{m}(K)$ over an arbitrary infinite field $K$ of odd characteristic. If $m$ is even, we show that each connected component of the orthogonal monoid is a normal variety; this implies that the orthogonal Schur algebra associated to the identity component is a

Graham G. Ross, Mario Serna

We propose an improved method for hadron-collider mass determination of new states that decay to a massive, long-lived state like the LSP in the MSSM. We focus on pair produced new states which undergo three-body decay to a pair of visible particles and the new invisible long-lived state. Our approach is to construct a kinematic quantity which enforces all k

Marek Biesiada, Aleksandra Piórkowska

Despite the fact that quantum gravity theory still remains elusive, it is generally expected that it will bring the picture of a space-time foam at short distances leading to Lorenz Invariance Violation (LIV) manifested e.g. by energy dependent modification of standard relativistic dispersion relation. One direction of research, pursued intensively is to mea

E. Pecou, B. Cessac, G. Espinoza

This paper has been withdrawn due to an error in the proof of the main theorem.

L. Benfatto, C. Castellani, T. Giamarchi

The energy needed to create a vortex core is the basic ingredient to address the physics of thermal vortex fluctuations in underdoped cuprates. Here we theoretically investigate its role on the occurrence of the Beresinskii-Kosterlitz-Thouless transition in a bilayer film with inhomogeneity. From the comparison with recent measurements of the penetration dep

Poul Olesen

The Makeenko-Migdal loop equation is non-linear and first order in the area derivative, but we show that for simple loops in QCD$_2$ it is possible to reformulate this equation as a linear equation with second order derivatives. This equation is a bound state Schrödinger equation with a three dimensional Coulomb potential. Thus, loop dynamics leads to a surp

The LEP Collaboration, ALEPH Collaboration, DELPHI Collaboration, L3 Collaboration

This note presents constraints on Standard Model parameters using published and preliminary precision electroweak results measured at the electron-positron colliders LEP and SLC. The results are compared with precise electroweak measurements from other experiments, notably CDF and DØat the Tevatron. Constraints on the input parameters of the Standard Model a

J. P. Pridham

We study the Galois actions on the l-adic schematic and Artin-Mazur homotopy groups of algebraic varieties. For proper varieties of good reduction over a local field K, we show that the l-adic schematic homotopy groups are mixed representations explicitly determined by the Galois action on cohomology of Weil sheaves, whenever l is not equal to the residue ch

F. S. Liu, X. Y. Xia, Shude Mao, Hong Wu

We investigate the photometric properties of the early type Brightest Cluster Galaxies (BCGs) using a carefully selected sample of 85 BCGs from the C4 cluster catalogue with redshift less than 0.1. We perform accurate background subtractions, and surface photometry for these BCGs to 25 $\magsec$ in the Sloan $r$-band. By quantitatively analysing the gradient

M. Palese, E. Winterroth

A reductive structure is associated here with Lagrangian canonically defined conserved quantities on gauge-natural bundles. Parametrized transformations defined by the gauge-natural lift of infinitesimal principal automorphisms induce a variational sequence such that the generalized Jacobi morphism is naturally self-adjoint. As a consequence, its kernel defi

N. N. Achasov, G. N. Shestakov

New high statistics Belle data on the $γγ\toπ^+π^-$ reaction cross section measured in the range of pion-pair invariant masses $\sqrt{s}$ between 0.8 GeV and 1.5 GeV are analyzed to clarify the current situation around the $σ(600)$, $f_0(980)$, and $f_2(1270)$ resonances in $γγ$ collisions. The present analysis shows that the direct coupling constants of the

A. Ciardi, D. J. Ampleford, S. V. Lebedev, C. Stehle

Herbig-Haro jets often show some degree of curvature along their path, in many cases produced by the ram pressure of a side-wind. We present simulations of both laboratory and astrophysical curved jets and experimental results from laboratory experiments. We discuss the properties and similarities of the laboratory and astrophysical flow, which show the form

Matthias Christandl, Ben Toner

We work in a general framework where the state of a physical system is defined by its behaviour under measurement and the global state is constrained by no-signalling conditions. We show that the marginals of symmetric states in such theories can be approximated by convex combinations of independent and identical conditional probability distributions, genera

Vadim Kostrykin, Jurgen Potthoff, Robert Schrader

The main objective of the present work is to study contraction semigroups generated by Laplace operators on metric graphs, which are not necessarily self-adjoint. We prove criteria for such semigroups to be continuity and positivity preserving. Also we provide a characterization of generators of Feller semigroups on metric graphs.

Alexey Veryaskin

A quantitative theory of operation of a novel device, namely Direct String Magnetic Gradiometer (DSMG), is presented. The paper provides a detailed analysis of DSMG basic functions and measured quantities, represented in terms of physical parameters that are known either a priori or can be experimentally determined. It leaves a reasonable degree of freedom t

Keisuke Izumi

We construct a five dimensional exact solution of the orthogonal black di-ring which has two black rings whose $S^1$-rotating planes are orthogonal. This solution has four free parameters which represent radii of and speeds of $S^1$-rotation of the black rings. We use the inverse scattering method. This method needs the seed metric. We also present a systema

L. Chevillard, C. Meneveau, L. Biferale, F. Toschi

Modeling the velocity gradient tensor A along Lagrangian trajectories in turbulent flow requires closures for the pressure Hessian and viscous Laplacian of A. Based on an Eulerian-Lagrangian change of variables and the so-called Recent Fluid Deformation closure, such models were proposed recently. The resulting stochastic model was shown to reproduce many ge

Giacomo M. D&#39;Ariano, Rafal Demkowicz-Dobrzanski, Paolo Perinotti, Massimiliano F. Sacchi

We address the general problem of removing correlations from quantum states while preserving local quantum information as much as possible. We provide a complete solution in the case of two qubits, by evaluating the minimum amount of noise that is necessary to decorrelate covariant sets of bipartite states. We show that two harmonic oscillators in arbitrary

M. Kostur, L. Machura, P. Talkner, P. Hanggi

We investigate classical anomalous electrical transport in a driven, resistively and capacitively shunted Josephson junction device. Novel transport phenomena are identified in chaotic regimes when the junction is subjected to both, a time periodic (ac) and a constant, biasing (dc) current. The dependence of the voltage across the junction on the dc-current

Taras Fityo

We considered the thermodynamics in spaces with deformed commutation relation leading to existence of the minimal length. We developed a classical method of the partition function evaluation. We calculated the partition function and heat capacity for ideal gas and harmonic oscillators using this method. The obtained results are in good agreement with the exa

K. A. Bronnikov, S. G. Rubin

We show that a number of problems of modern cosmology may be addressed and solved in the framework of multidimensional gravity with high-order curvature invariants, without invoking other fields. As applications of this approach, we mention primordial inflation and particle production after it; description of the modern accelerated stage of the Universe with

Pinaki Chaudhuri, Yongxiang Gao, Ludovic Berthier, Maria Kilfoil

We study the heterogeneous dynamics of attractive colloidal particles close to the gel transition using confocal microscopy experiments combined with a theoretical statistical analysis. We focus on single particle dynamics and show that the self part of the van Hove distribution function is not the Gaussian expected for a Fickian process, but that it reflect

Priyam Das, Manan Vyas, Prasanta K Panigrahi

In a one-dimensional shallow optical lattice, in the presence of both cubic and quintic nonlinearity, a superfluid density wave is identified in a Bose-Einstein condensate. Interestingly, it ceases to exist when only one of these interactions is operative. We predict the loss of superfluidity through a classical dynamical phase transition, where modulational

Diptiman Sen, Michael Stone, Smitha Vishveshwara

We study various geometrical aspects of the propagation of particles obeying fractional statistics in the physical setting of the quantum Hall system. We find a discrete set of zeros for the two-particle kernel in the lowest Landau level; these arise from a combination of a two-particle Aharonov-Bohm effect and the exchange phase related to fractional statis

J. M. Harrison

The article surveys quantization schemes for metric graphs with spin. Typically quantum graphs are defined with the Laplace or Schrodinger operator which describe particles whose intrinsic angular momentum (spin) is zero. However, in many applications, for example modeling an electron (which has spin-1/2) on a network of thin wires, it is necessary to consid

C. J. Burden

The Affymetrix U95 and U133 Latin Square spike-in datasets are reanalysed, together with a dataset from a version of the U95 spike-in experiment without a complex non-specific background. The approach uses a physico-chemical model which includes the effects the specific and non-specific hybridisation and probe folding at the microarray surface, target foldin

R. Harris, M. W. Johnson, S. Han, A. J. Berkley

Macroscopic resonant tunneling between the two lowest lying states of a bistable RF-SQUID is used to characterize noise in a flux qubit. Measurements of the incoherent decay rate as a function of flux bias revealed a Gaussian shaped profile that is not peaked at the resonance point, but is shifted to a bias at which the initial well is higher than the target

B. C. Allanach, C. H. Kom

We perform a quantitative study of neutrino phenomenology in the framework of minimal supergravity (mSUGRA) with grand unified theory (GUT)-scale tri-linear lepton number violation. We show that only two non-zero GUT scale lepton number violating parameters and three charged lepton mixing angles are sufficient to account for current neutrino oscillation data

David J. Schwab, Robijn F. Bruinsma, Joseph Rudnick, Jonathan Widom

We present a statistical-mechanical analysis of the positioning of nucleosomes along one of the chromosomes of yeast DNA as a function of the strength of the binding potential and of the chemical potential of the nucleosomes. We find a significant density of two-level nucleosome switching regions where, as a function of the chemical potential, the nucleosome

L. Berlyand, V. Rybalko

We study solutions of the 2D Ginzburg-Landau equation -Δu+\frac{1}{\ve^2}u(|u|^2-1)=0 subject to &#34;semi-stiff&#34; boundary conditions: the Dirichlet condition for the modulus, |u|=1, and the homogeneous Neumann condition for the phase. The principal result of this work shows there are stable solutions of this problem with zeros (vortices), which are loca

Y. Aoki, P. A. Boyle, N. H. Christ, C. Dawson

We present a calculation of the renormalization coefficients of the quark bilinear operators and the K-Kbar mixing parameter B_K. The coefficients relating the bare lattice operators to those in the RI/MOM scheme are computed non-perturbatively and then matched perturbatively to the MSbar scheme. The coefficients are calculated on the RBC/UKQCD 2+1 flavor dy

F. Moreno-Insertis, K. Galsgaard, I. Ugarte-Urra

Recent observations of coronal hole areas with the XRT and EIS instruments onboard the Hinode satellite have shown with unprecedented detail the launching of fast, hot jets away from the solar surface. In some cases these events coincide with episodes of flux emergence from beneath the photosphere. In this letter we show results of a 3D numerical experiment

M. R. Meyer, J. M. Carpenter, E. E. Mamajek, L. A. Hillenbrand

We report observations from the Spitzer Space Telescope (SST) regarding the frequency of 24 micron excess emission toward sun-like stars. Our unbiased sample is comprised of 309 stars with masses 0.7-2.2 Msun and ages from <3 Myr to >3 Gyr that lack excess emission at wavelengths <=8 microns. We identify 30 stars that exhibit clear evidence of excess emissio

David H. Cohen, Maurice A. Leutenegger, Richard H. D. Townsend

By quantitatively fitting simple emission line profile models that include both atomic opacity and porosity to the Chandra X-ray spectrum of $ζ$ Pup, we are able to explore the trade-offs between reduced mass-loss rates and wind porosity. We find that reducing the mass-loss rate of $ζ$ Pup by roughly a factor of four, to 1.5 \times 10^{-6} M_sun/yr, enables

Stefano Marmi, Piergiulio Tempesta

A generalization of the classical Lipschitz summation formula is proposed. It involves new polylogarithmic rational functions constructed via the Fourier expansion of certain sequences of Bernoulli--type polynomials. Related families of one--dimensional hyperfunctions are also constructed.

K. K. Gan

The on-detector optical link of the ATLAS pixel detector contains radiation-hard receiver chips to decode bi-phase marked signals received on PIN arrays and data transmitter chips to drive VCSEL arrays. The components are mounted on hybrid boards (opto-boards). We present results from the irradiation studies with 24 GeV protons up to 32 Mrad (1.2 x 10^15 p/c

J. L. Marshall

I develop a new technique to identify M-type extreme subdwarfs (esdMs) and demonstrate that it is substantially more efficient than previous methods. I begin by obtaining spectroscopy and improved photometry of a sample of 54 late-type halo candidates using the rNLTT reduced proper motion (RPM) diagram. From spectroscopy, I find that four of these are esdMs,

So Takei, Yong Baek Kim

We study the effects of dissipation and time-independent nonequilibrium drive on an open superconducting graphene. In particular, we investigate how dissipation and nonequilibrium effects modify the semi-metal-BCS quantum phase transition that occurs at half-filling in equilibrium graphene with attractive interactions. Our system consists of a graphene sheet

C. Megan Urry, E. Treister

In recent years deep X-ray and infrared surveys have provided an efficient way to find accreting supermassive black holes, otherwise known as active galactic nuclei (AGN), in the young universe. Such surveys can, unlike optical surveys, find AGN obscured by high column densities of gas and dust. In those cases, deep optical data show only the host galaxy, wh

Rosalba Perna, Roberto Soria, Dave Pooley, Luigi Stella

Traditionally, studies aimed at inferring the distribution of birth periods of neutron stars are based on radio surveys. Here we propose an independent method to constrain the pulsar spin periods at birth based on their X-ray luminosities. In particular, the observed luminosity distribution of supernovae poses a constraint on the initial rotational energy of

Jon Handy

Let $K$ be a square Cantor set, i.e. the Cartesian product $K=E\times E$ of two linear Cantor sets. Let $δ_n$ denote the proportion of the intervals removed in the $n$th stage of the construction of $E$. It is shown that if $δ_n=o(\frac1{\log\log n})$ then the corona theorem holds on the domain $Ω=\mathbb C^\ast\setminus K$.

Gregory Dobler, Douglas P. Finkbeiner

We study the spectral and morphological characteristics of the diffuse Galactic emission in the WMAP temperature data using a template-based multi-linear regression, and obtain the following results. 1. We confirm previous observations of a bump in the dust-correlated spectrum, consistent with the Draine & Lazarian spinning dust model. 2. We also confirm the

J. P. Dietrich

We study the dependence of citation counts of e-prints published on the arXiv:astro-ph server on their position in the daily astro-ph listing. Using the SPIRES literature database we reconstruct the astro-ph listings from July 2002 to December 2005 and determine citation counts for e-prints from their ADS entry. We use Zipf plots to analyze the citation dist

José Bernabéu, Catalina Espinoza

The ultimate goal for future neutrino facilities is the determination of CP violation in neutrino oscillations. Besides $| U(e3) | \ne 0$, this will require precision experiments with a very intense neutrino source and energy control. With this objective in mind, the creation of monochromatic neutrino beams from the electron capture decay of boosted ions by

Jack Morava

This is a historical talk about the recent confluence of two lines of research in equivariant elliptic cohomology, one concerned with connected Lie groups, the other with the finite case. These themes come together in (what seems to me remarkable) work of N. Ganter, relating replicability of McKay-Thompson series to the theory of exponential cohomology opera

M. Agundez, J. P. Fonfria, J. Cernicharo, J. R.

We report on the detection of vinyl cyanide (CH2CHCN), cyanomethyl radical (CH2CN), methylacetylene (CH3CCH) and thioformaldehyde (H2CS) in the C-rich star IRC +10216. These species, which are all known to exist in dark clouds, are detected for the first time in the circumstellar envelope around an AGB star. The four molecules have been detected trough pure

Nicolas Yunes, Carlos F. Sopuerta

We study perturbations of a Schwarzschild black hole in Chern-Simons modified gravity. We begin by showing that Birkhoff&#39;s theorem holds for a wide family of Chern-Simons coupling functions, a scalar field present in the theory that controls the strength of the Chern-Simons correction to the Einstein-Hilbert action. After decomposing the perturbations in

Mu Zhu

Since their emergence in the 1990&#39;s, the support vector machine and the AdaBoost algorithm have spawned a wave of research in statistical machine learning. Much of this new research falls into one of two broad categories: kernel methods and ensemble methods. In this expository article, I discuss the main ideas behind these two types of methods, namely ho

S. M. Kozyrev

The interpretations of solutions of Einstein field&#39;s equations led to the prediction and the observation of physical phenomena which confirm the important role of general relativity, as well as other relativistic theories in physics. In this connection, the following questions are of interest and importance: whether it is possible to solve the gauge prob

Timoteo Carletti, Duccio Fanelli, Alessio Guarino, Franco Bagnoli

We here discuss the process of opinion formation in an open community where agents are made to interact and consequently update their beliefs. New actors (birth) are assumed to replace individuals that abandon the community (deaths). This dynamics is simulated in the framework of a simplified model that accounts for mutual affinity between agents. A rich phe

Ahmed Ali

We review the salient features of $B$-meson physics, with particular emphasis on the measurements carried out at the $B$-factories and Tevatron, theoretical progress in understanding these measurements in the context of the standard model, and anticipation at the LHC. Topics discussed specifically are the current status of the Cabibbo-Kobayashi-Maskawa matri

CLEO Collaboration, S. Dobbs

Using a sample of 1.8 million DDbar meson pairs collected at the psi(3770) with the CLEO-c detector, we study the semileptonic decays D^0 -> pi^- e^+ nu_e, D^+ -> pi^0 e^+ ν_e, D^0 -> K^- e^+ ν_e, and D^+ -> Kbar^0 e^+ nu_e. For the total branching fractions we find B(D^0 -> pi^- e^+ ν_e) = 0.299(11)(9)%, B(D^+ -> pi^0 e^+ ν_e) = 0.373(22)(13)%, B(D^0 -> K^-

Udai Raj Singh, S. Chaudhuri, Shyam K. Choudhary, R. C. Budhani

Variable temperature scanning tunneling microscopy/spectroscopy studies on (110) oriented epitaxial thin films of La$_{0.350}$Pr$_{0.275}$Ca$_{0.375}$MnO$_3$ are reported in the temperature range of 77 to 340 K. The films, grown on lattice matched NdGaO$_3$ substrates, show a hysteretic metal-insulator transition in resistivity at 170 K. The topographic STM

A. D. Kennedy, T. Binoth, T. Rippon

We give an overview of state-of-the-art multi-loop Feynman diagram computations, and explain how we use symbolic manipulation to generate renormalized integrals that are then evaluated numerically. We explain how we automate BPHZ renormalization using &#34;henges&#34; and &#34;sectors&#34;, and give a brief description of the symbolic tensor and Dirac gamma-

D. Mundarain, J. Stephany

In this report we consider the three dimensional subset of the space of states of two qubits that may be written in the so called standard form. For those states we show that different measures of entanglement, specifically concurrence, negativity and the Hilbert-Schmidt distance are proportional to the euclidean distance between the point representing the s

A. V. Tserunyan

For a given graph consider a pair of disjoint matchings the union of which contains as many edges as possible. Furthermore, consider the relation of the cardinalities of a maximum matching and the largest matching in those pairs. It is known that this relation does not exceed 5/4 for any graph. We characterize the class of graphs for which this relation is p

Peter Horn

We introduce a geometric invariant of knots in the three-sphere, called the first-order genus, that is derived from certain 2-complexes called gropes, and we show it is computable for many examples. While computing this invariant, we draw some interesting conclusions about the structure of a general Seifert surface for some knots.

Jian-Ge Zhou, Quinton L. Williams, Frank Hagelberg

We demonstrate for the first time that when a methanethiol adsorbed on the regular Cu(111) surface, the dissociative structure is thermodynamically more stable than the intact one. The computational results show that at low temperature the methanethiol adsorbate prefers the atop site of the regular Cu(111) surface. As the temperature is increased, the S-H bo

R. Somma, S. Boixo, H. Barnum

We develop a quantum algorithm to solve combinatorial optimization problems through quantum simulation of a classical annealing process. Our algorithm combines techniques from quantum walks, quantum phase estimation, and quantum Zeno effect. It can be viewed as a quantum analogue of the discrete-time Markov chain Monte Carlo implementation of classical simul

Anna Levina, J. Michael Herrmann, Theo Geisel

We show that a network of spiking neurons exhibits robust self-organized criticality if the synaptic efficacies follow realistic dynamics. Deriving analytical expressions for the average coupling strengths and inter-spike intervals, we demonstrate that networks with dynamical synapses exhibit critical avalanche dynamics for a wide range of interaction parame

P. Chomaz, F. Gulminelli

(abridged) In this paper, we present the issues we consider as essential as far as the statistical mechanics of finite systems is concerned. In particular, we emphasis our present understanding of phase transitions in the framework of information theory. Information theory provides a thermodynamically-consistent treatment of finite, open, transient and expan

Jie Sun, Peng Jin, Zhanguo Wang

Self-assembled semiconductor quantum dot is a new type of artificially designed and grown function material which exhibits quantum size effect, quantum interference effect, surface effect, quantum tunneling-Coulumb-blockade effect and nonlinear optical effect. Due to advantages like less crystal defects and relatively simpler fabrication technology, that mat

D. Cronin-Hennessy, CLEO Collaboration

Using 1.8 million DDbar pairs and a neutrino reconstruction technique, we have studied the decays D^0 -> K^- e^+ nu_e, D^0 -> pi^- e^+ nu_e, D^+ -> Kbar^0 e^+ nu_e, and D^+ -> pi^0 e^+ nu_e. We find B(D^0 -> pi^- e^+ nu_e) = 0.299(11)(9)%, B(D^+ -> pi^0 e^+ nu_e) = 0.373(22)(13)%, B(D^0 -> K^- e^+ nu_e) = 3.56(3)(9)%, and B(D^+ -> Kbar^0 e^+ nu_e) = 8.53(13)

Kai Johannes Keller, Nikolaos A. Papadopoulos, Andrés F. Reyes-Lega

The aim of this paper is to give a simple, geometric proof of Wigner&#39;s theorem on the realization of symmetries in quantum mechanics that clarifies its relation to projective geometry. Although several proofs exist already, it seems that the relevance of Wigner&#39;s theorem is not fully appreciated in general. It is Wigner&#39;s theorem which allows the

S. S. Avancini, J. R. Marinelli, D. P. Menezes, M. M. W. Moraes

We calculate the skin thickness, binding energy, surface energy and density profiles within the Dirac solution of a density dependent hadronic model and compare with the NL3 parametrization results of the non-linear Wallecka model. The asymmetry for polarized electron scattering is also obtained using a partial wave expansion calculation. Results for 208Pb,

T. Kawaguchi, K. Nakanishi, K. Kohno, K. Ohta

In order to investigate how the growth of galactic bulges progresses with the growth of central black holes (BHs), we observed molecular gas (fuel for the coming star formation) in possibly young active galaxies, narrow-line Seyfert 1 galaxies (NLS1s). We present the results of radio observations of 12CO(1--0) using the Nobeyama Millimeter Array (with 2--4 k

K. Ropotenko

For an ordinary thermodynamical system the Poincaré recurrence time is exponentially large in the Boltzmann entropy of the system. It turns out, that for a system with dynamical chaos it is determined by the Kolmogorov-Sinai entropy and can be considerably shorter. It is shown in this note that for the de Sitter space with strong mixing properties the mean r

E. Rasanen, H. Saarikoski, A. Harju, M. Ciorga

Two-dimensional semiconductor quantum dots are studied in the the filling-factor range 2<v<3. We find both theoretical and experimental evidence of a collective many-body phenomenon, where a fraction of the trapped electrons form an incompressible spin-droplet on the highest occupied Landau level. The phenomenon occurs only when the number of electrons in th

Dagomir Kaszlikowski, Marcin Wiesniak

In this short note we discuss the relation between the so-called Off-Diagonal-Long-Range-Order in many-body interacting quantum systems introduced by C. N. Yang in Rev. Mod. Phys. {\bf 34}, 694 (1962) and entanglement. We argue that there is a direct relation between these two concepts.

A. R. Witham, C. Knigge, J. E. Drew, R. Greimel

We present a catalogue of point-source Halpha emission line objects selected from the INT/WFC Photometric H$\alpha$ Survey of the Northern Galactic Plane (IPHAS). The catalogue covers the magnitude range 13 < r' < 19.5 and includes northern hemisphere sources in the Galactic latitude range -5 < b < 5 degress. It is derived from ~1500 square degress worth of

A. E. Kyprianou, J. C. Pardo

In this paper, for $α\in (1, 2}$ we show that the $α$-stable continuous-state branching process and the associated process conditioned never to become extinct are positive self-similar Markov processes. Understanding the interaction of the Lamperti transformation for continuous-state branching processes and the Lamperti transformation for positive self-simil

Mieczyslaw K. Dabkowski, Makiko Ishiwata, Jozef H. Przytycki

We start a systematic analysis of links up to 5-move equivalence. Our motivation is to develop tools which later can be used to study skein modules based on the skein relation being deformation of a 5-move (in an analogous way as the Kauffman skein module is a deformation of a 2-move, i.e. a crossing change). Our main tools are Jones and Kauffman polynomials

Lars Bergstrom

A brief review of the indirect detection signatures of dark matter is given. In particular, detection methods of dark matter particle annihilation to antimatter and gamma-rays are reviewed. With the GLAST satellite soon to be launched, a crucial window in the energy range of a few GeV up to 300 GeV will open. The good angular and energy resolution of the ins

D. E. Innes

Concentrations of molecular hydrogen (H2) have been detected by SUMER in active region plage. The H2 is excited by O VI line emission at 1031.94 A which, although not observed, must be brightening along with the observed transition region line, Si III 1113.24 A. We have made co-ordinated observations of active region plage with the spectrometer SUMER/SoHO in